# 解法1
# import turtle
#
# size=150
# angle=360//8  # 风轮的角数45度
# turtle.pensize(2)
# turtle.right(90)
# for i in range(4):
#     turtle.circle(size,45)
#     turtle.penup()
#     turtle.circle(size, 45)
#     turtle.pendown()
#
# turtle.goto(size*2,0)
# turtle.penup()
# turtle.goto(size,-size)
# turtle.pendown()
# turtle.goto(size,size)
# turtle.penup()
# turtle.goto(size,0)#回圆心
# turtle.pendown()
# turtle.right(45)
# turtle.fd(size)
# turtle.bk(size*2)
# turtle.goto(size,0)#回圆心
# turtle.right(90)
# turtle.fd(size)
# turtle.penup()
# turtle.back(size*2)
# turtle.pendown()
# turtle.fd(size)
# turtle.done()

# 解法2 老师的解法
# import turtle as t
# t.pensize(2)
# for i in range(4):
#     t.seth(90*i)
#     t.fd(150)
#     t.right(90)
#     t.circle(-150, 45)
#     t.goto(0,0)
# turtle.done()

# 解法3 4扇风叶的固定画法
# import turtle
# size=150
# sides=8
# angle=360//sides  # 风轮的角数
#
# turtle.pensize(2)
# for i in range(sides//2):
#     turtle.fd(size)
#     turtle.right(90)
#     turtle.circle(-size, angle)
#     turtle.goto(0, 0)
#     turtle.left(angle)
# turtle.left(angle*3)
# turtle.done()

# 解法4 n扇风叶的画法
import turtle
radius=150 #风轮半径
sides=eval(input("请输入风轮扇叶数:"))  # 风轮的扇叶
angle=180/sides  # 每片扇叶的角度
turtle.pensize(2)
for i in range(sides):
    turtle.fd(radius)
    turtle.right(90)
    turtle.circle(-radius, angle)
    turtle.goto(0, 0)
    turtle.left(90-angle)

turtle.left(angle*3)
turtle.done()